namespace Fusion.Addons.KCC
{
	using UnityEngine;

	public sealed class KCCShapeCastInfo
	{
		// PUBLIC MEMBERS

		public Vector3                 Position;
		public float                   Radius;
		public float                   Height;
		public float                   Extent;
		public Vector3                 Direction;
		public float                   MaxDistance;
		public LayerMask               LayerMask;
		public QueryTriggerInteraction TriggerInteraction;
		public KCCShapeCastHit[]       AllHits;
		public int                     AllHitCount;
		public KCCShapeCastHit[]       ColliderHits;
		public int                     ColliderHitCount;
		public KCCShapeCastHit[]       TriggerHits;
		public int                     TriggerHitCount;

		// PRIVATE MEMBERS

		private static readonly float[] _sortDistances = new float[KCC.CACHE_SIZE];

		// CONSTRUCTORS

		public KCCShapeCastInfo() : this(KCC.CACHE_SIZE)
		{
		}

		public KCCShapeCastInfo(int maxHits)
		{
			AllHits      = new KCCShapeCastHit[maxHits];
			TriggerHits  = new KCCShapeCastHit[maxHits];
			ColliderHits = new KCCShapeCastHit[maxHits];

			for (int i = 0; i < maxHits; ++i)
			{
				AllHits[i] = new KCCShapeCastHit();
			}
		}

		// PUBLIC METHODS

		public bool HasCollider(Collider collider)
		{
			for (int i = 0, count = AllHitCount; i < count; ++i)
			{
				KCCShapeCastHit hit = AllHits[i];
				if (object.ReferenceEquals(hit.Collider, collider) == true)
					return true;
			}

			return false;
		}

		public bool HasCollider(EColliderType colliderType)
		{
			for (int i = 0, count = AllHitCount; i < count; ++i)
			{
				KCCShapeCastHit hit = AllHits[i];
				if (hit.Type == colliderType)
					return true;
			}

			return false;
		}

		public void AddHit(RaycastHit raycastHit)
		{
			if (AllHitCount == AllHits.Length)
				return;

			KCCShapeCastHit hit = AllHits[AllHitCount];
			if (hit.Set(raycastHit) == true)
			{
				++AllHitCount;

				if (hit.IsTrigger == true)
				{
					TriggerHits[TriggerHitCount] = hit;
					++TriggerHitCount;
				}
				else
				{
					ColliderHits[ColliderHitCount] = hit;
					++ColliderHitCount;
				}
			}
		}

		public void Sort()
		{
			int count = AllHitCount;
			if (count <= 1)
				return;

			bool              isSorted   = false;
			bool              hasChanged = false;
			KCCShapeCastHit[] allHits    = AllHits;
			float[]           distances  = _sortDistances;
			int               leftIndex;
			int               rightIndex;
			float             leftDistance;
			float             rightDistance;
			KCCShapeCastHit   leftHit;
			KCCShapeCastHit   rightHit;

			for (int i = 0; i < count; ++i)
			{
				distances[i] = allHits[i].RaycastHit.distance;
			}

			while (isSorted == false)
			{
				isSorted = true;

				leftIndex    = 0;
				rightIndex   = 1;
				leftDistance = distances[leftIndex];

				while (rightIndex < count)
				{
					rightDistance = distances[rightIndex];

					if (leftDistance <= rightDistance)
					{
						leftDistance = rightDistance;
					}
					else
					{
						distances[leftIndex]  = rightDistance;
						distances[rightIndex] = leftDistance;

						leftHit  = allHits[leftIndex];
						rightHit = allHits[rightIndex];

						allHits[leftIndex]  = rightHit;
						allHits[rightIndex] = leftHit;

						isSorted   = false;
						hasChanged = true;
					}

					++leftIndex;
					++rightIndex;
				}
			}

			if (hasChanged == true)
			{
				TriggerHitCount  = 0;
				ColliderHitCount = 0;

				KCCShapeCastHit hit;

				for (int i = 0; i < count; ++i)
				{
					hit = allHits[i];

					if (hit.IsTrigger == true)
					{
						TriggerHits[TriggerHitCount] = hit;
						++TriggerHitCount;
					}
					else
					{
						ColliderHits[ColliderHitCount] = hit;
						++ColliderHitCount;
					}
				}
			}
		}

		public void Reset(bool deep)
		{
			Position           = default;
			Radius             = default;
			Height             = default;
			Extent             = default;
			Direction          = default;
			MaxDistance        = default;
			Radius             = default;
			LayerMask          = default;
			TriggerInteraction = QueryTriggerInteraction.Collide;
			AllHitCount        = default;
			ColliderHitCount   = default;
			TriggerHitCount    = default;

			if (deep == true)
			{
				for (int i = 0, count = AllHits.Length; i < count; ++i)
				{
					AllHits[i].Reset();
				}
			}
		}

		public void DumpHits(KCC kcc)
		{
			if (AllHitCount <= 0)
				return;

			kcc.Log($"ShapeCast Hits ({AllHitCount})");

			KCCShapeCastHit[] hits = AllHits;
			for (int i = 0, count = AllHitCount; i < count; ++i)
			{
				KCCShapeCastHit hit = AllHits[i];
				kcc.Log($"Collider: {hit.Collider.name}, Type: {hit.Type}, IsTrigger: {hit.IsTrigger}, Distance: {hit.RaycastHit.distance}");
			}
		}
	}
}